1. Field of the Invention
The present invention relates to an image pickup apparatus using a solid-state image pickup element, such as a CCD.
2. Description of the Related Art
In general, solid-state image pickup elements, such as CCDs, are presently used as light receiving elements of image pickup apparatuses. In the field of HDTV (High Density Television) or the like, it has been required to improve the image quality of such a solid-state image pickup element to meet a demand for increasing the resolution of TV signals, and there have been attempts to improve the image quality by increasing the number of pixels of the solid-state image pickup element. Although such an attempt needs a further improvement of manufacturing techniques, it is impossible to improve them to an unlimited extent.
In such a situation, it has recently been proposed to provide a system for improving the resolution of an image by swinging a solid-state image pickup element to temporarily vary a relative positional relation between an incident optical image and individual pixels and increasing a spatial sampling ratio (the Journal of the Institute of Television Engineers of Japan, Vol. 41, No. 11 (1987)).
Various methods for producing a panoramic video image have heretofore been known, and one proposed method is described in Japanese Laid-Open Patent Application No. Sho 54-3526. This method includes the steps of photographing a subject about the optical axis of a photographic lens of a camera by means of a rotating mirror disposed on a subject side of the camera coaxially to the photographic lens with its reflecting surface opposed to the camera, processing the exposed film to form an intermediate image representative of a panoramic subject image which is recorded in compressed form, loading the film which carries the obtained intermediate image into an enlarger, and projecting the intermediate image on an enlarged scale onto a photosensitive member formed cylindrically around a rotating mirror, by means of the rotating mirror which is disposed coaxially to the enlarging lens and is of the same kind as the aforesaid rotating mirror, thereby producing a panoramic subject image.
However, there are a number of problems in the above-described system for improving the resolution of an image, which adopts an arrangement in which the solid-state image pickup element is made to vibrate periodically by a small amount by a piezoelectric element. For example, highly accurate positioning is needed to incorporate such an arrangement into an optical system, but this positioning is difficult to conduct and is disadvantageous in terms of productivity. In addition, a package having a special structure which involves a great increase in cost is needed to mount the solid-state image pickup element.
The above-described conventional method for producing a panoramic video image has the problem that it is necessary to incorporate a complicated mechanism in the camera since photography is performed by means of the rotating mirror disposed coaxially to the photographic lens on the subject side thereof. In addition, if a panoramic video image is to be actually produced, it is necessary to modify an existing enlarger.